The human visual system is faced with the computationally difficult problem of recognizing objects despite potentially large changes in image position, scale, viewpoint, and illumination. The ability to maintain 'object constancy' is crucial to our survival, allowing us to perceive and interact with a stable, predictable, and familiar environment. Despite its importance, how the visual system achieves object constancy is largely unknown. We propose a series of behavioral and functional MRI (fMRI) experiments aimed at characterizing the neural mechanisms underlying object recognition during changes in viewing conditions. In the first series of experiments, we aim to characterize neural responses to image transformations including rotation, scale, and position. The second set of experiments will build on the results of the first by assessing the role of attention and expectation on behavioral and neural responses. The final set of experiments will attempt to specify the role of learning and experience in the development of object perceptions and transformation-invariant neural responses. In all of the experiments, we will use a novel fMRI adaptation technique to characterize tuning functions in specified visual areas.